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  <title>The MongoDB\BSON\Decimal128 class</title>
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    <li>The MongoDB\BSON\Decimal128 class</li>
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 <h1 class="title">The MongoDB\BSON\Decimal128 class</h1>
 

 <div class="partintro"><p class="verinfo">(mongodb &gt;=1.2.0)</p>


  <div class="section" id="mongodb-bson-decimal128.intro">
   <h2 class="title">简介</h2>
   <p class="para">
    BSON type for the
    <a href="https://en.wikipedia.org/wiki/Decimal128_floating-point_format" class="link external">&raquo;&nbsp;Decimal128 floating-point format</a>,
    which supports numbers with up to 34 decimal digits (i.e. significant
    digits) and an exponent range of −6143 to +6144.
   </p>
   <p class="para">
    Unlike the double BSON type (i.e. <span class="type">float</span> in PHP), which only
    stores an approximation of the decimal values, the decimal data type stores
    the exact value. For example, <code class="literal">MongoDB\BSON\Decimal128(&#039;9.99&#039;)</code>
    has a precise value of 9.99 where as a double 9.99 would have an approximate
    value of 9.9900000000000002131628….
   </p>
   
   <blockquote class="note"><p><strong class="note">注意</strong>: 
    <span class="simpara">
     <span class="classname"><strong class="classname">MongoDB\BSON\Decimal128</strong></span> is only compatible with
     MongoDB 3.4+. Attempting to use the BSON type with an earlier version of
     MongoDB will result in an error.
    </span>
   </p></blockquote>

  </div>


  <div class="section" id="mongodb-bson-decimal128.synopsis">
   <h2 class="title">类摘要</h2>


   <div class="classsynopsis">
    <div class="ooclass"></div>


    <div class="classsynopsisinfo">
     <span class="modifier">final</span>
     <span class="ooclass">
      <span class="modifier">class</span> <strong class="classname">MongoDB\BSON\Decimal128</strong>
     </span>

     <span class="oointerface"><span class="modifier">implements</span> 
       <a href="class.mongodb-bson-decimal128interface.html" class="interfacename">MongoDB\BSON\Decimal128Interface</a></span><span class="oointerface">,  <a href="class.mongodb-bson-type.html" class="interfacename">MongoDB\BSON\Type</a></span><span class="oointerface">,  <a href="class.serializable.html" class="interfacename">Serializable</a></span><span class="oointerface">,  <a href="class.jsonserializable.html" class="interfacename">JsonSerializable</a></span><span class="oointerface">,  <a href="class.stringable.html" class="interfacename">Stringable</a></span> {</div>


    <div class="classsynopsisinfo classsynopsisinfo_comment">/* 方法 */</div>
    <div class="methodsynopsis dc-description">
   <span class="modifier">final</span> <span class="modifier">public</span> <span class="methodname"><a href="mongodb-bson-decimal128.construct.html" class="methodname">__construct</a></span>(<span class="methodparam"><span class="type">string</span> <code class="parameter">$value</code></span>)</div>
<div class="methodsynopsis dc-description"><span class="modifier">final</span> <span class="modifier">public</span> <span class="methodname"><a href="mongodb-bson-decimal128.jsonserialize.html" class="methodname">jsonSerialize</a></span>(): <span class="type"><a href="language.types.declarations.html#language.types.declarations.mixed" class="type mixed">mixed</a></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">final</span> <span class="modifier">public</span> <span class="methodname"><a href="mongodb-bson-decimal128.serialize.html" class="methodname">serialize</a></span>(): <span class="type">string</span></div>
<div class="methodsynopsis dc-description"><span class="modifier">final</span> <span class="modifier">public</span> <span class="methodname"><a href="mongodb-bson-decimal128.tostring.html" class="methodname">__toString</a></span>(): <span class="type">string</span></div>
<div class="methodsynopsis dc-description"><span class="modifier">final</span> <span class="modifier">public</span> <span class="methodname"><a href="mongodb-bson-decimal128.unserialize.html" class="methodname">unserialize</a></span>(<span class="methodparam"><span class="type">string</span> <code class="parameter">$serialized</code></span>): <span class="type"><span class="type void">void</span></span></div>

   }</div>


  </div>

  <div class="section">
   <h2 class="title">更新日志</h2>
   <p class="para">
    <table class="doctable informaltable">
     
      <thead>
       <tr>
        <th>版本</th>
        <th>说明</th>
       </tr>

      </thead>

      <tbody class="tbody">
       <tr>
        <td>PECL mongodb 1.12.0</td>
        <td>
         Implements <span class="interfacename"><a href="class.stringable.html" class="interfacename">Stringable</a></span> for PHP 8.0+.
        </td>
       </tr>

       <tr>
        <td>PECL mongodb 1.3.0</td>
        <td>
         Implements <span class="interfacename"><a href="class.mongodb-bson-decimal128interface.html" class="interfacename">MongoDB\BSON\Decimal128Interface</a></span>.
        </td>
       </tr>

       <tr>
        <td>PECL mongodb 1.2.0</td>
        <td>
         Implements <span class="interfacename"><a href="class.serializable.html" class="interfacename">Serializable</a></span> and
         <span class="interfacename"><a href="class.jsonserializable.html" class="interfacename">JsonSerializable</a></span>.
        </td>
       </tr>

      </tbody>
     
    </table>

   </p>
  </div>

 </div>

 







 






 






 






 







<h2>目录</h2><ul class="chunklist chunklist_reference"><li><a href="mongodb-bson-decimal128.construct.html">MongoDB\BSON\Decimal128::__construct</a> — Construct a new Decimal128</li><li><a href="mongodb-bson-decimal128.jsonserialize.html">MongoDB\BSON\Decimal128::jsonSerialize</a> — Returns a representation that can be converted to JSON</li><li><a href="mongodb-bson-decimal128.serialize.html">MongoDB\BSON\Decimal128::serialize</a> — Serialize a Decimal128</li><li><a href="mongodb-bson-decimal128.tostring.html">MongoDB\BSON\Decimal128::__toString</a> — Returns the string representation of this Decimal128</li><li><a href="mongodb-bson-decimal128.unserialize.html">MongoDB\BSON\Decimal128::unserialize</a> — Unserialize a Decimal128</li></ul>
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